Sylvain Charlebois knows a thing or two about food. He's a professor at Dalhousie University in Halifax, Canada, and tweets as @FoodProfessor. So, what does he think about the current global food crisis?

It started two years ago, when COVID disrupted supply chains, but the acute shortages that are driving up prices are more recent, he explained in a conversation for GZERO with Diana Fox Carney, Senior Advisor at Eurasia Group.

Why? Charlebois cites climate issues that hurt inventories, higher shipping costs due to the COVID hangover of weakened supply chains, Russia's war in Ukraine pushing prices up across the board, and "nationalistic hoarding" of staples by certain countries.